Questions tagged [gpio]
GPIO is an acronym for general purpose input/output. The term is typically applied to a pin on a microcontroller (or other device) that may be changed between an input and output under software control. It can be used for an application defined purpose, as opposed to being constrained to a single designated function.
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SPI DAC7800 output incorrect (bipolar mode) — UPD signal timing vs CS, Orin Nano SPI + gpiod
I’m working with a DAC7800KU on a custom board and using an NVIDIA Jetson Orin Nano as the SPI master via /dev/spidev0.0. The DAC output doesn’t match the expected voltage even though the SPI transfer ...
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How does this (active low triggered) circuit work?
I suspect this question will be trivial for many of you, but I haven't been able to find any answer online that satisfies my curiosity. I have an ACTIVE LOW relay module that connects to a GPIO [...
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How should the ST pin be connected for TPS2117 power switching in priority mode (if Vin1 is connected, it is set as output)?
I am trying to build a circuit that takes one of two 5V inputs; it should output Vin1 if it is connected, and otherwise output Vin2. Here is an image of the circuit I designed using information from ...
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Will ESP32-C3-WROOM be able to keep the TPS61040DBVR IC off in deep sleep mode?
I'm told that GPIO3 is an RTC pin, capable of saving its state even if the ESP32-C3 enters deep sleep mode. Here's my thinking: I want to have the chip on by default, so I'll pull the EN pin high ...
1 vote
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Zener Diode Causing 3.3V Regulator Overload – Need Safe GPIO Protection Options
3.3V regulator becomes very hot until I remove diodes D104, D105, D106, and D107. These are BZT52C3V6-HE3-08 Zener diodes with a Zener voltage of 3.6V. In addition to the regulator heating up, the ...
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A relay diagram that I will run with the Raspberry Pi 4 Model B GPIO pins
Is the circuit shown in the image suitable for driving a relay with a Raspberry Pi 4 Model B? Will high voltage and current damage my Raspberry Pi 4 Model B device? Will it cause damage when used with ...
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What is needed to convert a 5V digital output to an audio line output?
I have a microcontroller pin that I will use for a simple square wave audio output. The gpio pin will be 5V high and the frequency will be in the audio range. The physical output may be an RCA style ...
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I2C Max30102 sensors not working on raspberry pi 5
I am trying to set up my raspberry pi 5 with the max30102 sensor via the i2c interface. I bought two sensors, but neither seem to work. I'm trying to rule out faulty sensors and I don't have a ...
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How to take a signal from GPIO pin and feed to a device with SMA input
A PCB with an FPGA is generating a pulse which is available on a JST connector GPIO pin. It is approx 30 ns wide, and repeats approx every 40,000 ns. The device for which this signal is destined has ...
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Can I power ds3231 from esp32 gpio pin?
Due to limitations in my compact PCB design, I can not draw a wire from VCC pin to DS3231 to power it up. But I can connect DS3231's Vcc pin to a GPIO pin of ESP32 (WROOM Module). Since according to ...
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Pi Pico GPIO1 transition very long compared to GPIO0
I've written a simple program the transitions GPIO0 and GPIO1 high to low and low to high "at the same time". The board is powered over USB and not connected to anything. I've got my ...
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GPIO Pins usage on the ESP-32 Cam
I am programming a remote controlled scooping robot with an esp32 cam. The idea is to drive the H-bridge motor driver using gpio 12,13,14,15. The scooping mechanism would be controlled using two ...
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Driving a halogen lamp (4.8 V, 0.5 A) with a GPIO pin of Raspberry Pi 4
I'm working on a project where I want to control a halogen lamp (Panasonic MB-48M5H) using a GPIO pin on a Raspberry Pi 4. Since a single GPIO pin can only source a maximum of 16 mA, and I plan to ...
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1 vote
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External resistor pull down values for STM32 gpio
While I play with STM32 a lot on the software side, I still miss a lot of hardware knowledge so I want to confirm my thinking before making a test PCB. I use STM32L4R5 GPIO to control LM3800 power ...
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Spurious rising edges on 20 meter long GPIO cables into Raspberry Pi via opto isolator
I have a number of binary input channels at 13.8v level running into a Raspberry Pi via a CNY74-4H Transistor Output Optocoupler. I have pull down resistors on the inputs to the Optocoupler, and I'm ...
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